Re: [PATCH v2 RESEND] fuse: Enable dynamic configuration of fuse max pages limit (FUSE_MAX_MAX_PAGES)

[Sweet Tea Dorminy <sweettea-kernel@dorminy.me>]

On 9/5/24 1:45 PM, Joanne Koong wrote:
> Introduce the capability to dynamically configure the fuse max pages
> limit (formerly #defined as FUSE_MAX_MAX_PAGES) through a sysctl.
> This enhancement allows system administrators to adjust the value
> based on system-specific requirements.
> 
> This removes the previous static limit of 256 max pages, which limits
> the max write size of a request to 1 MiB (on 4096 pagesize systems).
> Having the ability to up the max write size beyond 1 MiB allows for the
> perf improvements detailed in this thread [1].
> 
> $ sysctl -a | grep max_pages_limit
> fs.fuse.max_pages_limit = 256
> 
> $ sysctl -n fs.fuse.max_pages_limit
> 256
> 
> $ echo 1024 | sudo tee /proc/sys/fs/fuse/max_pages_limit
> 1024
> 
> $ sysctl -n fs.fuse.max_pages_limit
> 1024
> 
> $ echo 65536 | sudo tee /proc/sys/fs/fuse/max_pages_limit
> tee: /proc/sys/fs/fuse/max_pages_limit: Invalid argument
> 
> $ echo 0 | sudo tee /proc/sys/fs/fuse/max_pages_limit
> tee: /proc/sys/fs/fuse/max_pages_limit: Invalid argument
> 
> $ echo 65535 | sudo tee /proc/sys/fs/fuse/max_pages_limit
> 65535
> 
> $ sysctl -n fs.fuse.max_pages_limit
> 65535
> 
> v2 (original):
> https://lore.kernel.org/linux-fsdevel/20240702014627.4068146-1-joannelkoong@gmail.com/
> 
> v1:
> https://lore.kernel.org/linux-fsdevel/20240628001355.243805-1-joannelkoong@gmail.com/
> 
> Changes from v1:
> - Rename fuse_max_max_pages to fuse_max_pages_limit internally
> - Rename /proc/sys/fs/fuse/fuse_max_max_pages to
>    /proc/sys/fs/fuse/max_pages_limit
> - Restrict fuse max_pages_limit sysctl values to between 1 and 65535
>    (inclusive)
> 
> [1] https://lore.kernel.org/linux-fsdevel/20240124070512.52207-1-jefflexu@linux.alibaba.com/T/#u
> 
> Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
> Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>

Thanks for doing this!!